The US State Department says an American who was among four peace activists kidnapped in Iraq last year has been killed.

Tom Fox was seized last November, along with Briton Norman Kember and Canadians James Loney and Harmeet Singh Sooden.

A video tape showing the other three men was released on Tuesday, but Fox did not feature on it.

Fox, 54, had been working with Iraqi human rights organisations for the past two years.

"The FBI verified the identity of a body found in Iraq this morning. While additional forensics will be completed in the United States, they believe this is the body of Tom Fox," said State Department spokesman Noel Clay.

"The family has been notified and our heartfelt condolences go out to the family."

Mr Fox's body was found on Friday morning, the State Department said, without saying where.